We propose to establish a high resolution, state of the art, facility for scanning electron microscopy at Case Western Reserve University for the use of the basic science departments of the School of Medicine. During the past few years all of the basic science departments have gone through a major renovation both of space and faculty which has led to a renaissance of basic cell and molecular biology on campus. High quality facilities are available for nearly every type of cellular study with the exception of scanning facilities. There are currently three scanning electron microscopes available in various locations within the medical school, but none of them is suitable for the kinds of microscopy possible today with high vacuum, cold stage, micromanipulators, and ion detectors. The major users of this new facility are involved in studies of a variety of cells in culture and the analysis of embryonic mutations. We anticipate considerably expanded use of the facility as further new faculty are recruited to the various cell and molecular programs in the basic sciences.